Coupling member



G. R. BAMBERGER 1 3" 2 v a M COUPLING MEMBER Filed Nov. 19, 1936 lily/$77107:

GlemlZBanzber 27* her over a relatively large area j Patented May 23, 1939 PATENT OFFICE COUPLING MEMBER Glenn R. Bamberger,

Sears, Roebuck and 00.,

tion of New York Chicago, Ill., assignor to Chicago, 111., a corpora- Application November 19, 1936, Serial No. 111,668

. 6 Claims.

, This invention relates to a coupling device I whichis especially adapted f vehicles as well as for the where a cable, rope, or

5 member is looped about be moved or supported.

, 1 An object of my invention is to provide a coupler of the type as to distribute other flexible tension an object intended to the strain on the tension ,mem-

of the member when the tension member engages the coupler, and thus to increase the life of said tension member.

Another object is to provide a hook which is so. constructed as not to out into the tension m mb r with which the hook may be employed when the member is subjected to tension, thereby increasing the safety factor of the tension mem- 1 ber. [Various other objects and advantages will bee come apparent as the description proceeds.

Referring now to the drawing illustrating a 4 preferred embodiment of the invention and form.-

] ing a part of this specification:

l 1 is an elevational view of a hook embodying the invention in cooperative relation with a tension member and with a member upon which a force is being applied, the latter being shown in cross section; 1

Fig. 2 is a side elevational view of the tow hook shown in Fig. 1; and

Fig. 3 is a sectional view along the'line 3-3 of Fig. 2.

The coupling member embodying the inven tion, as illustrated in the drawing, comprises an eyeportion l0 and a hook portion l2 which may be cast from metal as an integral unit. The eye portion I0 is provided with an opening M for take substantially receiving the tension member l6 such as a rope p or cable, which may be connected with the coubeing looped through the eye,

as at 20.

plingmember by as at 18, and spliced The hook portion ures 2 and 3 of the drawing, is provided with an inner, bearing surface 24 which is broadened, so as to increase the bearing area, and is also formed so as to slope obliquely with reference to the major axis of the device. The slope of the surface 24 indicated by the angle 0, is so designed as to reduce the angle taken by the standing end of the tension member l6 when the latter is engaged by the hook portion l2 and a force is applied to the free end of said tension member, as shown in Fig. l.

"1 The curvature of the surface 24 provides for for the towing of lifting of weights, etc, v

referred to which is so designed I2, as clearly shown in Figa gradual bending of the tension member l6 rather than the usual abrupt bending of the tension member. a

The side edges 26 of the hook portion I 2 are rounded and continuous with the surface 24 for further reducing any cutting tendency of the hook on the tension member. It, will be noted that the lower part of the hook portion I 2 between the side edges 26 and the rounded heel 28 isprovided with concavities 30 which results in the edges26 being in the nature of ribs for providing a hook portion having the maximum strength in proportion to theamount of material employed. 1

Laboratory experiments have shown that when devices embodying the present invention are em-, ployed, vastly increased loads may be applied to a rope or other tension member, as compared with other types of hooks, before failure of the tension member occurs.

As illustrated, the inner bearing surface 24 of the open eye of the coupling device may intersect the median plane of said device and may be generally frusto-conical, the leading end 26 of said surface (at left in Fig. 3) being closer than the trailing end 26 (at right in Fig. 3) to the axis of the closed eye, and the trailing end of said surface may be inclined substantially 30 to a linenormal to the median plane of the device. It will be noted from the drawing that the lower part, i. e., the heel, of the open eye may be of generally triangular cross-section, with a side of the triangle constituting an element of the bearing surface 24 and the vertex opposite said side lying substantially in the median plane of the open eye. As shown, the open eye may be relatively narrow transversely of the median plane of the device, with the greatest width of the open eye at its heel, said open eye tapering substantially to a point at the free end thereof.

Various changes coming within the spirit of the invention may be suggested by those skilled in the art, and hence I do not wish to be limited to the specific forms shown or uses mentioned, except to the extent indicated by the appended claims, which are to be interpreted as broadly as the state of the art will permit.

I claim:

l. A one-piece coupling device comprising an attenuated piece of metal lying in substantially one plane and curled into an endless integrallyclosed eye and an open eye, said open eye having an approximately straight tension member compensating for the flattenin bearing surface inclined ing through said plane.

2. A one-piece coupling device comprising a closed eye and a hook portion with an open eye, said eyes lying in substantially the same median plane, said open eye having a generally frustoconical inner tension member bearing surface which is inclined to and intersects said median plane and is slightly convex longitudinally, the longitudinally spaced ends of said surface being disposed beyond the planes of the ends of the axis of said closed eye, said ends of said surface being rounded away from said open eye, the lead: ing end of said surface being closer'than the transversely to and passtrailing end of said surface to the axis of said closed eye, the leading end of said surface being substantially tangent and the trailing end of said surface being substantially 30 to a line normal to said median plane, whereby said surface has intimate bearing contact throughout its length with and brings about a gradual b ending .of a tension member connected to said closed eye and looped about an object to be pulled, the heel of said hook portion being concavely rounded ad jacent and below said ends of said'surface, forming strengthening ribs at said ends, and convexly rounded between and below the concavities to provide an outer peripheral strengthening rib I g of said surface.

3, A one-piece coupling device comprising a closed eye and a hook portion with an open eye, said eyes lying in substantially the same median plane, said open eye having a generally frustoconical inner tension member bearing surface which is inclined to and intersects'said median plane and is slightly convex longitudinally, the

longitudinally spaced ends of said surface being disposed beyond the planes .of' the ends of the axis of said closed eye, said ends of said surface being rounded away from said open eye, the leading end of said surface being closer than the trailing end of said surface to the axis of said closed eye, whereby said surface has intimate bearing contact throughout its length with and sa ed f f om and y n n and tapering substantially to a brings about a gradual bending of a tension member connected to said closed eye and looped about an object'to be pulled, the heel of said hook portion being concavely rounded adjacent and below said ends of said surface, forming strengthening ribs at said ends, and convexly rounded between and below the concavities to provide an outer peripheral strengthening rib compensating for the flattening of said surface.

4. A coupling device comprising a casting having a hook portion having an open eye and an anchoring portion adapted for connection to a ension member, the heel of said eye having a generally triangular cross section with a side of the triangle constituting an element of the tension member bearing surface, said surface being inclined to and the vertex opposite said surface lying substantially in the median plane of said eye.

5. A coupling device comprising a closed eye pon ion, an open eye portion extending in elonthe median plane of said closed eye portion, said open eye portion being relatively narrow transversely of said plane and having its greatest width at the heel thereof point at the free end thereof, said heel having a tension member bearing surface at the widest portion thereof, said surface being approximately flat transversely of said heel and inclined to and intersecting said plane.

6. A coupling device comprising a closed eye portion, an open eye portion extending in elon, gated form from and lying in the median plane of said closed eye portion, said open eye portion being relatively narrow transversely of said plane, and having its greatest width at the heel thereof and tapering substantially to a point at the free end thereof, said surface being inclined to and intersecting said plane and being of slight convexity transversely of and between the sides of said heel and of relatively pronounced convexity at the junctures of said surface with said sides.

R. BAMBERGER. 

